This invention relates to a rotary cutting machine for cutting vegetable products and the like into a plurality of smaller pieces of desired size and shape. More particularly, this invention relates to an improve rotary cutting machine for slicing a vegetable product, such as a potato, into a plurality of elongated thin strips or shreds for use, for example, in the formation of hashbrawn potato patties or the like.
Rotary cutting or slicing machines in general are well known in the art, and typically comprise a radially open impeller mounted for rotation within a stationary outer housing. See, for example, U.S. Pat. No. 3,139,128. The product is fed axially into the interior of the impeller which throws the product by centrifugal force in a radially outward direction into engagement with a circumferentially arranged set of cutting knives carried by the outer housing. A plurality of paddles secured to the periphery of the impeller carry the product rotationally about the interior of the housing into sequential cutting engagement with the cutting knives for cutting the product into a plurality of smaller pieces.
Rotary cutting machines of this general type have been used to cut or slice a variety of vegetable products into smaller pieces having a variety of different sizes and shapes, depending upon the particular shape of the product fed to the machine and the particular configuration of the various cutting knives. For example, the machine can be adapted to slice whole potatoes into a plurality of slabs, French fry strips, or the like. Alternately, the machine can be adapted to cut potato pieces such as slabs or strips into other shapes such as elongated thin shreds to form hashbrown potatoes or the like.
For many vegetable products, it is desirable to orient the outer housing and the impeller with respect to a vertical axis, and to supply the product by gravity in a downward direction into the machine. With this arrangement, the impeller throws the product in a radially outward and generally horizontal direction toward the outer housing and the cutting knives, with at least some uniformity of product distribution about the circumference of the housing. However, when the product is relatively small in size, such as when potato slabs or slices are provided for cutting into thin shreds, it has been found that the product falls directly to the bottom of the impeller and is thrown radially outwardly into engagement primarily with only the lower portion of each cutting knife. This undesirably limits the maximum production rate of the machine and results in relatively rapid wear of the lowermost portions of the cutting knives, thereby requiring relatively frequent stoppage of production to change or sharpen the knives. Moreover, since the product is typically supplied to the impeller in surges, a relatively large drive motor is required for continuous and substantially constant speed impeller rotation without stalling or overloading of the motor.
An additional problem encountered with prior art rotary cutting machines is that the product tends to orient at random for cutting by the cutting knives along the various longer and shorter dimensions of the product. That is, the various ones of the product are cut generally at random along their length, width, or thickness, resulting in an uncontrolled size distribution among the cut product pieces. For some vegetable products having significantly variant dimensions, this lack of control over the final size distribution can be highly undesirable. For example, when potato slabs or slices are cut into smaller potato shreds to form hashbrown potatoes, it is important to minimize the distribution of shorter-length pieces to improve the overall appearance of the final product. Moreover, in potato products, the formation of a substantial proportion of shorter-length pieces results in the release of undesirable quantities of free starch which can detrimentally affect the taste and appearance of the final product.
The present invention overcomes the problems and disadvantages of the prior art by providing an improved rotary cutting machine including apparatus for dividing the product for generally uniform engagement along the length of each cutting knife, and further including means for orienting the product with respect to the cutting knives for substantially increasing the proportional distribution of longer-length product pieces.